Wood County reporter. [volume] (Grand Rapids [i.e. Wisconsin Rapids], Wis.) 1857-1923, 1887-07-28
The Great American Lakes.

1t has long been known that the great
lakes are subject to remarkable and
seemingly capricious changes of level
| These changes are roughly registered
in the varying volume of the St Law.
renee that remarkable river, itself
the outlet of these great lakes and in a
sense continuation and part of the
lakes themselves. In some years the
St Lawrence, which drains a water
shed OF over 100000 square miles. is
much fuller all summer than in other
years.
This almost incomprehensible mass
OF water, the drainage or overflow of
all the great lakes, varies in volume
with the level of the lakes of which If
is part A Milwaukee paper gives
some interesting facts relating to these
mysterious irregular tidal movements.
or changes of level, in Lake Michigan.
This, the second in size and depth of
these great lakes-the largest bodies
OF fresh water on the globe-is subject
| to strange fluctuations, being several
feet lower in some years than in others.
Lake Michigan is deep lake about
a thousand feet deep, or practically as
deep as Lake Superior. 1t has been,
it seems, for nearly thirty years the
practice of the government to take
daily measurements of the height of
the water at Milwaukee. The water
which at that point Gas the clinging
| memory of a plunge into it at the close
CT July, 1S49, still attests) is almost as
icy cold as it is at MackinaW-isu usual
ly foot or two higher in summer than
it is in winter, but in some wears the
variation is equal to three or four feet.
Ihls represents, on so great body of
water, an enormous difference Lake
Superior alone is almost as large as
the great state of Ohio, while Lake
Michigan, the direct receiver of its
overflow, is about as large as Massa-
chusett9, Vermont, and New Hamp-
shire put together. A change of three
or four feet in the level of these great
lakes implies a difference in the amount
OF water too great to be fully under
stood and appreciated. The other
lakes necessarily participate in the
fluctuations, but these appear to be
most marked in Lake Michigan.
Their cause is not yet wholly under
stood. Various theories have been adj
vanced to account for them-even to
the absurd extent of connecting them
with the ocean tidal movements. But
far simpler explanation seems more
probable. 1t would seem that the
higher level in lake Michigan in sum-
mer and autumn may be caused by the
spring and summer rains and late
melting SHOWS of the vast Canadian
watershed which feeds Lake Superior
II to II; e.e,+,,
rivers. In that immense lake rise of
a single foot is equivalent to q much
greater rise in the lesser lakes of the
great system. That the fluctuations
should be irregular, showing a far
greater level in some years than in 9TH
ers, might we'll be due to the varying
quantities of May and June rain in diff
ferent years, and to the greater guam
titles Of snow remaining in those hyper
bOrean ATTITUDES, to be only transform
ed, in May and June, into water Of
course the influx received by the larger
lake would be far less in winter-and |
hence the lakes would be lowest in
winter and highest in summer and au-
tumn. Whatever the cause may be, !
the occurrence itself of these large
fluctuations in the levels of such vast
bodies of water is one of the striking
facts in the worlds greatest fresh-wat-
er system, and well worthy of philo- !
sOphical examination. That lake and |
river system-or perhaps it might be
called all one great river, two thous-
and miles long-is the notwithstanding
one on the globe. Its greatest expan-
sion-the vast Lake Superior-is at a |
level Of over 600 feet above the sea; a |
lake whose area is 81, 500 square miles
in extent, and whose depth is thous-
and feet. The river flows on it's lordly |
course through the rocks of the Lau-
rentian system, the oldest on the globe, |
and it receives as its affluent the dark, |
wild waters of the Sagueney.- Hart-
ford Times.